It is standard to mount curtains on hangers that slide in overhead-mounted guide rails. The longitudinally extending guide rails form a downwardly open and longitudinally extending slot and each rail has a pair of longitudinally extending upwardly directed support faces flanking the slot. The hangers each have a head longitudinally displaceable inside the rails on the support faces thereof, a body projecting through the slot downward out of the rails, and a horizontally projecting guide flange immediately below the rails and at a predetermined spacing below the head. The curtain is normally suspended from loops on the lower ends of the hangers. Thus it is possible to open and close the curtains by sliding the hangers along the rails. Since the hangers are guided inside the rails, the installation is very neat and can blend into any decor.
The main problem with these systems is in the transition from rail to rail. Ideally it is merely necessary to butt the rails and secure them solidly so that the joints between rail ends is closed and the hangers do not catch on them. If, however, there is any vertical or horizontal misalignment, or if the rails are not perfectly aligned, the hangers can catch at a joint, making the installation inoperative.